第六十八篇: 全球变暖

The average for the day was 399.73 and researchers at the observatory expect this figure, too, to exceed 400 in the next few days.

这天的平均浓度为399.73ppm。观测站研究人员预计，在接下来的几天，该数值将会超过400ppm。

The Arctic, by contrast, gets a lot of polluted air from Europe and North America.

相比之下，北极有大量来自欧洲与北美洲的污染空气。

The last time such values prevailed on Earth was in the Pliocene epoch,4m years ago, when jungles covered northern Canada.

距离上一次地球上出现这样的浓度，是在4百万年以前的上新世时期，那时候，加拿大北部地区被大片丛林所覆盖。

Mauna Loa is the benchmark for CO2 measurement (and has been since 1958, see chart) because Hawaii is so far from large concentrations of humanity.

莫纳罗亚地区是二氧化碳测量基准（从1958年以来就是如此，如图所示）。这是因为夏威夷远离人类大规模的聚齐地。

This year the average reading for the whole month will probably also reach 400ppm, according to Pieter Tans, who is in charge of monitoring at Mauna Loa, and the seasonally adjusted annual figure will reach 400ppm in the spring of 2014 or 2015.

据在莫纳罗亚负责监控的Pieter Tans称，今年5月的平均浓度可能也会达到400ppm，而在2014年或2015年的春季，数值将会达到400ppm。

AT NOON on May 4th the carbon dioxide concentration in the atmosphere around the Mauna Loa Observatory in Hawaii hit 400 parts per million (ppm).

5月4日中午，夏威夷莫纳罗亚观测站测量到在其附近大气层中，二氧化碳的浓度达到了400ppm。

Mauna Loa’s readings are one of the world’s longest-running measurement series.

莫纳罗亚测量的测量值是世界上使用时间最长的测量标准之一。